ABSTRACT Anger and aggression are serious and frequent complicating factors in the treatment of post-traumatic stress disorder (PTSD). Interpersonal aggression and anger are: i) strongly associated with PTSD (Orth & Wieland, 2006; Taft et al, 2012); ii) particularly pernicious among individuals with combat-related PTSD (Novaco & Chemtob, 2002); and, iii) critical barriers to effective treatment in combat-related PTSD (Forbes et al., 2003; Forbes et al., 2008). Anger and aggression can also critically damage the interpersonal relationships of veterans; these relationships are essential to the social support necessary for recovery of functioning (Beckham et al., 1997; Carlson et al., 2008; Elbogen et al., 2008; Frueh et al., 1997; 2001; Chemtob et al., 1997; Freeman & Roca, 2001; Gerlock, 1994; Glenn et al., 2002; Lasko et al., 1994; Taft et al., 2005, 2007a; 2007b; Monson & Taft, 2005). Despite the detrimental impact that anger and aggression have on the lives of combat veterans with PTSD, and despite the barrier that anger and aggression pose to treatment and recovery, very little is understood about the neural substrates underlying interpersonal aggression in PTSD, or the neural mechanisms that promote recovery for veterans with difficulties with anger and aggression. In previous work, our team has developed Trauma Management Therapy (TMT), a multicomponent psychotherapy for chronic, Vietnam-era veterans with PTSD targeting both fear and anxiety symptoms, as well as interpersonal dysfunction (Frueh et al., 1996; Beidel, Frueh et al., 2011). Though this treatment is supported by results of a small RCT among chronic Vietnam-era veterans, its efficacy has not been evaluated among younger, less chronic veterans returning from OEF/OIF/OND. In separate work, we have identified mechanisms of interpersonal aggression, cooperation, and emotional dysregulation in OEF/OIF/OND veterans with PTSD (see Preliminary Data; King-Casas & Chiu, 2012; King-Casas et al., 2005; Zhu et al., in preparation; Lindsey et al., 2010). However, the role that these mechanisms play in the treatment and recovery is unknown. Here, we propose to leverage these two lines of research to (i) evaluate the efficacy of Trauma Management Therapy (TMT) for the treatment of PTSD in OEF/OIF/OND veterans who are younger and have had a less chronic course of illness than Vietnam era veterans with PTSD, and (ii) evaluate neural mediators of clinical improvements associated with TMT.